1. Field of the Invention
The present invention relates to a process of electrolytically manufacturing screen material by depositing a metal upon a matrix in an electrolytic bath, the latter containing at least one brightener.
2. Description of the Prior Art
U.S. Pat. No. 2,226,384 entitled Process of electrolytically producing foraminous sheets, issued to Edward D. Norris on Dec. 24, 1940, describes a process of forming a screen by electrolytically depositing a metal upon a screen skeleton formed in a first stage. The screen formed by electrolytically depositing a metal on the screen skeleton can be removed, if required, by previously applying a stripping means, e.g. beeswax, to the screen skeleton. Evidently in that case the parts of the skeleton not belonging to the separating surface must be coated with an insulating mass preventing deposition of metal on these parts in order to avoid a complete surrounding of the skeleton by deposited metal.
The drawback of this known process is that during the electrolytic deposition the lands as present in the matrix or screen skeleton grow in all directions, so that the screen material as finally obtained presents small passages with lands of substantially circular cross-section.